Published on May 31, 2010

The Morphing City is a visualization study where a city mutates its shape accordingly with the traffic on its main arteries. Those morphs tend to traduce the actual perceived distances within a city, bypassing the common perception based on its geographical mapping.

This visualization model was executed for the city of Lisbon. To attain it, topological information was gathered from OpenStreetMap to build a skeleton for the city based on its main arteries. The bones of the skeleton are springs that get compressed or distended accordingly with the detected velocities over it. Those distortions affect all the neighboring points and springs as the system is all interconnected.

The data concerning the velocities was gathered in the context of the CityMotion project, and it pays respect to 1534 vehicles in the city of Lisbon during October 2009. That data was averaged to a single day, and aggregated by periods of one hour. Those periods overlap in 50min, meaning that they are iterated by ticks of 10min.

What is being displayed are the distortions on each artery that affect the entire city. If the current speed on that artery is below its average global speed, the artery is compressed (the higher the velocity, the smaller the perceived distance). Similarly, if the speed is over the computed (during pre processing) global average, the artery is distended. The colors also reflect those distortions, with positive deviations traducing warm colors, and negative deviations traducing cold colors.

Another way to perceive the morphs in the city during the day it’s the deformed grid on the bottom right corner of the video (and below — distorted grid at 17h).

It’s interesting to notice how the city stays compressed during the evening, and how it abruptly expands during the rush hours: 8h-9h and 18h-19h. It’s also interesting to see that the 8h-9h period is by far the most problematic.